The present invention relates to apparatus for marking limp sheet material such as woven or nonwoven fabrics utilized in manufacturing garments, upholstery, and similar articles. More particularly, the invention relates to a marking apparatus that utilizes a thread having a dye thereon or impregnated therein so that drawing thread through the fabric material produces a mark for later identifying a key location on the material.
It has been common practice in the garment manufacturing industry to cut pattern pieces for clothing, upholstery, and the like from a multi-ply layup of fabric material. More recently, numerically controlled cutting mechines such as disclosed in U.S. Pat. No. 3,495,492 issued to the assignee of the present invention have been developed to cut pattern pieces with savings in time, increased accuracy and reduced waste material. The cut pattern pieces are then removed from the cutting machine and are taken to a sewing room where the various pieces are assembled as finished articles.
In assembling the various pattern pieces, certain key points such as the corners of pockets, intersections of seams, the location of buttonholes or shaping seams and similar points of interest within the contours of the pattern pieces are important.
Manual marking of the key points within pattern pieces has been done in the past by lacing colored thread through a stack of identical pattern pieces at the point of interest and then snipping a short segment of the thread with each pattern piece removed from the stack so that the thread remains with the pattern piece at a key point until the sewing operation associated with the point is begun. In other forms of thread marking, a dye such as a fluorescent dye, is applied to the thread and the thread is worked manually back and forth through the stack of pattern pieces at a key point to rub the dye onto the material and develop a mark. Such dye is later washed out or otherwise removed from the finished article.
With the advent of automatically controlled cutting machines, it readily became apparent that the marking operation could be performed by the same basic machine which performs the cutting operation under numerical control. U.S. Pat. Nos. 3,548,502 and 3,731,648 both disclose numerically controlled apparatus adapted for such marking functions. In the latter Pat. No. 3,731,648 having the same assignee as the present invention, a hollow needle is plunged through the stack of pattern pieces and a flowable marking material is deposited throughout the stack as the needle is withdrawn. When individual pattern pieces are removed from the stack, a small quantity of the marking material adheres to the pattern pieces at the points of interest. The marking of fabric material by means of a dye thread, however, has the advantage of producing a mark which can be brushed or washed off or otherwise removed from the material without great difficulty after the garment or upholstery is assembled. Thus, it is desirable to adapt an automatically controlled machine to utilize a needle which penetrates a dye thread through the stack of pattern pieces at points of interest. U.S. Pat. No. 3,765,349 discloses an apparatus for inserting thread through a stack of pattern pieces but not for the purpose of marking.
It is accordingly, a general object of the present invention to provide a marking apparatus which may be utilized on an automatically controlled cutting machine and which is adapted to plunge dye thread through a stack of pattern pieces at points of interest.